Sterilizer



J. B. PENTZ Aug. 11, 1953 STERILIZER Filed June 28, 1948 WATER LEVELINVENTOR Mm @/Lm;

ATTORNEY Patented Aug. 11, 1953 UNITED vSTATES* PATENT OFFICE James B.Pentz, Staten Island, N. Y. Application .time .28, 194s, serial No.35,553

1 The invention is concerned with methods of sterilization by means ofsuperheated steam and with apparatus connected therewith. Moreespecially, it is concerned with the cover of such apparatus. The covermay be employed in combination with steam chests such as the ordinarytype of sterilizer or the autoclave sterilizer where steam is held underpressure. It is also adapted to various types of cookers. y

The main object of the invention is to reduce if not to eliminate thecondensation of steam in a conventional steam chest when provided with aremovable cover. As the cover 4extends over an air space which acts asan insulator between it and the portion usually referred to as theboiler, and as the cover is often open, condensation of the steam comingin contact with the cooler surface of the cover is unavoidable,resulting in defective lasepsis because of the drippings from thecover.r I have found that it isthis failure of the heat in the cover toat least equal the heat ofthe walls ofthe steam chest which isresponsible for this vdefective asepsis.) kI have also found that thedefects are Aimmediately 'corrected by jacking up the heat inthecover'by means independent of the conventional boiling process. Thisnovel attack of the problem not only allows surgical instruments placedin the steam chest to become thoroughly sterilized,

but eliminates permeation of moisture and dripwe n ping of water intosuch articles as-surgical dressings placed in the steam chest. What'v isno'less important is that these results are lobtained'fin so short aspace of time that it Well may besaid that they are instantaneous.

In accordance with the above stated object, I provide the cover of mysteam chest with a hot plate, usually by means of an electric currentpassing through a resistance wire in the well known manner. The hotplate may be either on the inside or on the outside of the cover, butalways in close contact therewith.

While my invention is herein illustrated mainly in its application topresent day sterilizers, it will be understood that the novel featuresembodied in the cover will be equally eflicient when the invention isapplied to steam chests of other description, as, for instance, pressurecookers. It will be understood, further, that the steam chest may be ofany suitable configuration, although here shown as cylindrical in form.

In present day practice, after the process of sterilization has beencompleted and the sterilized articles are about to be removed from thesteam chest, the operator, upon removing the cover, finds the inside ofthe cover thoroughly 1 Claim. (o1. 21-95) v 2 saturated with condensedsteam which apt to drip back into the sterilizer or fall to the floor ofthe room. f

It also has been found that the surgical dressings, which usually areplaced in a tray near the top of the sterilizer adjacent the inside ofthe cover, become contaminated by the condensations dripping from thecover, especially while the cover is being removed.

The present invention obviates all of the above difficulties byproviding an electrical heating unit in close contact with the coverwhich keeps the entire lsterilizer' equally heated and does away withany cool portion Where the steam may condense and drip back into thesurgical,dressings.l Furthermore, in my process no air pockets areformed adjacent the cool cover which tend to delay orA frustratesterilization. It has been mentioned before that the heating unit may beunderneath the cover or over it, but in all cases it must be in closecontact with the cover. Other objects and advantages of the invention,not specifically mentioned above, will become apparent from thespecification which follows and from the accompanying drawing, in vwhichFigure 1 is a vertical cross section of a sterilizer embodying thepresent invention, with the usual, standard valves and additionalfeatures and xturesomitted for thesake of clarity.

' Figure 2 is a modied form of the invention, also shown in verticalcross section.

Figure 3 is a similar cross section of aV type of the invention providedwith the preferred form Qfcover U y L Figurelv is 'a top plan view ofthe electrical element used for heating the various covers.

Figure 5 shows the present invention adapted to a deep Well pressurecooker.

Referring to the drawing in detail, in Figure 1 there is shown in adiagrammatic Way a conventional sterilizer comprising a chest I0 havinga base portion II and a cover I2, with the usual heating element I3 in achamber I4 at the base II of the chest I0. The chest I 0 is providedwith brackets I5 and I6 secured therein for supporting a pair ofremovable trays I'I and I8. These trays have openings I9 for thereception of hooks for placing them into and removing them out of thechest I0. The trays I'I are used for holding surgical instruments, andthe trays I8 are for bandages and other surgical dressings to besterilized. The cover I2, which may be hinged or bolted to the chest I0,contains a heating unit I3 in a chamber 2|, formed by the shield I2'.The shield l2' may be provided With perforations along its upper surfaceto allow heat to escape, or it may be omitted altogether. The shield I2is removably secured to the cover I2 in any suitable manner by meansomitted from the drawing. When the steam strikes the inner surface 40 ofthe cover I2, the cover is heated by the heating element I3', whichprevents the condensation of steam on the surface 40, so that no watermay drip onto the bandage tray I8 during sterilization and no Water willdrip to the iioor when the cover I2 is removed from the chest I aftersterilization.

The heating elements I3 and I3' are preferably circular in plan andcross section and are sheathed or covered with an insulating material22. The terminals of the heating elements are adapted to be connected toa plug 23 which, in turn, is connected to the house current. When theshield I2 is omitted, the heating unit is exposed. It may be of anysuitable form. In some cases, it may be provided by a flat iron.

The apparatus may be used both for sterilization with steam, in whichcase the water in the steam chest is heated by the electric element I3,or for dry heat sterilization, in which case the chest is emptied of theWater, as by means of a petcock 4I shown in Figure 1. When sterilizingby steam, the level of the water is usually maintained above the tray I1which holds the surgical instruments. When sterilization is done by dryheat, the surgical dressings are placed in the upper tray I8, the heatagain being applied through the electrical element I3, but an absorbingpad 42, preferably of asbestos, is placed over the element I3. Toprevent the burning out of the heat element, the absorbing pad 42 iskept moist by allowing water to drip onto it from the cup 24.

In the modified form of sterilizer shown in Figure 2, the tray I8containing the surgical dressings may be dry heat sterilized in aseparate container 25 having an exposed heating unit 26 connected to aplug 2l. In this modification, it is immaterial whether the steam chestis emptied of water or not, in so far as sterilization of surgicaldressings is concerned.

The container 25 is flared at the base to snugly fit over the shield I2'and may be removed by the bail 28. In this type of the invention, thecircular brackets 23 may be interrupted so that the interrupted flangein the tray I8 may be inserted from the bottom of the container 25 androtated for locking and removing.

Figure shows a type adapted to a pressure cooker 30 which may or may notbe of the deep Well character. The cooker is shown seated in 4 anelectric range 3| which has an independent electrical heating unit 32.

In the type illustrated in Figure 3, the cover comprises a dome 32 and aflange 33 which may or may not be bolted to the steam chest I0. Itconsists of metal plates 34 and 35 which are sealed together at theflanged portion 33 but separated at the dome portion to form a chamber38 for accommodating a heating unit I3. To prevent air pockets whichoften are formed during sterilization at or near the cover of the steamchest, the steam which enters the chamber 36 through the upper port 31causes the heavier air to be driven out through the lower port 38, theseports being provided in the absorbing lining 39 and the metal plate 35.

Many variations in the structure of the device and in the character anddisposition of its elements may be made by those skilled in the artWithout departing from the substance and spirit of the invention, thescope of which is cOvered by the claim which follows.

I claim:

In a steam chest for sterilizing surgical instruments and dressings, aremovable top cover for said chest, spaced trays for respectivelyholding said instruments and dressings, said tray for said dressingsbeing disposed above said other tray and adjacent said cover, and meansin contact with said cover for heating said dressings independently ofthe steam in said chest.

JAMES B. PENTZ.

References Cited n the file of this patent UNITED STATES PATENTS NumberName Date 553,561 Lundholm Jan. 28, 1896 802,601 Scanlan Oct. 24, 19051,122,271 Golden Dec. 29, 1914 1,744,854 Zinna Jan. 28, 1930 1,830,287Ohlin Nov. 3, 1931 1,969,614 Klopfenstein Aug. 7, 1934 1,975,082 BucyOct. 2, 1934 2,047,973 Lawton et al. July 21, 1936 2,085,573 ButtolphJune 29, 1937 2,240,001 Harvey Apr. 29, 1941 2,362,117 David Nov. 7,1944 2,415,238 Emerson Feb. 4, 1947 OTHER REFERENCES The Principles andPractice of Textile Printing, by Knecht and Fothergill, third edition,Charles Griffen and Company, Ltd., London, 1936, see page 184.

